Thickness-dependent structural and electrical properties of multiferroic Mn-doped BiFeO3 thin films grown epitaxially by pulsed laser deposition

Thickness dependence of structural and electrical properties of multiferroic Mn-doped BiFeO3 (BFMO) thin films, grown on SrTiO3 (001) substrates with a bottom electrode of SrRuO3, was investigated. Very good ferroelectric properties were obtained in the thicker BFMO films with a typical remanent polarization of similar to 65 mu C/cm(2), while ferroelectric polarization switching was too difficult to detect using a conventional technique in the thinnest BFMO films due to a much higher coercive field and an increase in the tunneling current. Their ferroelectric nature, however, was demonstrated by piezoresponse force microscopy, and excellent insulating properties and homogeneity were achieved in the films. (C) 2008 American Institute of Physics.